The now multistate outbreak of L. monocytogenes consists of two clusters of illnesses that are likely linked to Blue Bell brand ice cream products. The outbreak involves eight people infected with outbreak strains of the bacterium; eight people are reported from Kansas (5) and Texas (3).

The federal health agency reports:

Cluster 1 consists of five patients reported from Kansas during January 2014 through January 2015 who were all hospitalized at a single hospital for unrelated problems before developing listeriosis. Of the four ill people for whom information is available on the foods eaten in the month before Listeria infection, all consumed milkshakes made at the hospital with a Blue Bell brand ice cream product called “Scoops.” Whole genome sequences of Listeria monocytogenes strains isolated from four of the patients were found to be highly related to sequences of Listeria strains isolated from “Scoops” and two other products made on the same line at the company’s Texas facility. These products were recalled by Blue Bell Creameries on March 13, 2015.

Cluster 2 consists of three patients reported from Texas during 2011 through 2014 who were all hospitalized for unrelated problems before developing listeriosis. Whole genome sequences of their Listeria monocytogenes strains were nearly identical to Listeria strains isolated from ice cream produced at the Blue Bell Creameries’ Oklahoma facility.

Texas health officials urge consumers to be aware of the Blue Bell Creameries recall and not to eat any product made at the company’s Oklahoma facility following listeria concerns.

Retailers are urged not to sell or serve products from the Oklahoma plant. They can be identified by checking for letters “O,” “P,” “Q,” “R,” “S” and “T” following the code date printed on the bottom of the product package. Consumers should discard or return Blue Bell products with those letters.

Persons who have the greatest risk of experiencing listeriosis after consuming foods contaminated with L. monocytogenes are fetuses and neonates who are infected after the mother is exposed to L. monocytogenes during pregnancy, the elderly, and persons with weakened immune systems.